Alanine aminotransferase (ALT) is commonly referred to as alanine aminotransferase (CPT), which is present in various tissue cells with the highest liver content, followed by cardiomyocytes, and low serum enzyme activity. When these tissues are diseased, cell necrosis or permeability is enhanced, intracellular enzymes are released into the blood, and serum ALT activity is increased. Serum ALT assay is mainly used for the diagnosis of liver disease.

Basic Information

Specialist classification: Digestive examination classification: liver function test

Applicable gender: whether men and women apply fasting: fasting

Analysis results:

Below normal:
No clinical significance.

Normal value:
Serum alanine aminotransferase: 5-40 U/L

Above normal:
Acute hepatitis is significantly elevated, especially for the early diagnosis of jaundice and asymptomatic hepatitis. ALT activity such as chronic hepatitis, cirrhosis, and liver cancer is slightly elevated. Biliary disease, myocardial and skeletal muscle damage can also cause elevated ALT.

negative:

Positive:

Tips: Before the examination, the diet is light and alcohol is prohibited. Check for an empty stomach in the morning. Normal value

(1) Colorimetric method for measuring 5 to 25 carmen units.

(2) Continuous monitoring method for adults 5 to 40 U/L (8 to 50 U/L when matrix contains P-5'-P).

Clinical significance

ALT measurement is of great value in the diagnosis, therapeutic observation and prognosis estimation of hepatitis.

(1) Acute hepatitis is significantly elevated, especially for the early diagnosis of jaundice and asymptomatic hepatitis. The positive rate is high, the positive time is earlier than other tests, and the activity level rises and falls with the progress and recovery of liver disease. According to this, the condition and prognosis can be observed. ALT continues to be at a high level or fluctuating repeatedly, indicating that the lesion is still ongoing or is converted to chronic hepatitis. If the jaundice is aggravated, ATL will decrease, the so-called "biliary enzyme separation" phenomenon, which is often a precursor to liver necrosis.

(2) ALT activity such as chronic hepatitis, cirrhosis, and liver cancer is slightly elevated.

(3) Biliary disease, myocardial and skeletal muscle damage can also cause elevated ALT.

High results may be diseases: hepatitis, neonatal hepatitis, pediatric glycogen storage disease type II, acute and chronic hepatitis precautions

Colorimetric determination:

(1) Severe jaundice, hemolysis, and lipemia specimens can make the measurement results high, and can be eliminated by using their own serum as a control.

(2) Specimens that exceed normal should be reviewed. After >150 U, the physiological saline solution is diluted and re-measured. The result is multiplied by the dilution factor.

(3) Regularly calibrate the instrument, sample applicator and pipette, and redraw the standard curve when changing the instrument or substrate fluid.

Inspection process

Immediately after venous blood collection, the test is performed. Detection method:

(1) Colorimetric method: The substrate solution was pre-warmed at 37 °C.

Mix, place 37% water bath for 20min, add 5ml of 0.4mol/L NaOH solution to each tube, mix well, set at room temperature for 5min, then adjust the zero point with the control tube at 505nm, read the absorbance of each tube, check the standard curve and get the ALT activity unit. .

(2) Continuous monitoring method: Each laboratory can be determined according to the analyzer model and operating instructions of this room. Main parameters: 340nm wavelength, 37 ° C, sample to reagent volume ratio of 1:10.

Not suitable for the crowd

Generally there are no special taboos.

Adverse reactions and risks

1. Infection: Pay attention to aseptic operation when collecting blood, avoid contamination of water and other parts at the blood collection site to avoid local infection.

2, bleeding: after the blood is given a full compression time, especially coagulopathy, bleeding tendency, to avoid local subcutaneous oozing, bruising and swelling.